Q: What are important aspects of safe infusion practice when administering IV vancomycin in the home?

Vancomycin is an intravenous (IV) antibiotic used to treat serious gram-positive infections including methicillin-resistant Staphylococcus aureus infections and gram-positive infections in patients with known allergies to penicillin and cephalosporins (Patel et al., 2022). Adverse reactions of vancomycin include nephrotoxicity, ototoxicity, and hypersensitivity reactions, both immunologic and nonimmunologic, including anaphylaxis. Vascular access related complications include thrombophlebitis and extravasation.

Vancomycin flushing syndrome (VFS), previously called "red man syndrome" is the most frequent adverse reaction, occurring in 4% to 50% of patients, with those under 40 years old at the highest risk (Martel et al., 2022). VFS is an infusion-related reaction caused by a release of histamine. VFS can be worse in patients being treated with other drugs including rifampin, cefepime, teicoplanin, ciprofloxacin, and amphotericin B. Symptoms include flushing, pruritus, and an erythematous rash on the face, neck, and upper torso. Hypotension may also occur as histamine is released. Although most VFS reactions are mild, reactions can also be life-threatening.

Symptoms of VFS can occur within 4 to 10 minutes after starting the infusion or shortly after infusion completion. It is important to recognize the correlation between the increased risk for VFS and infusion rate. Vancomycin should never be administered in less than 60 minutes.

Should your patient show signs of VFS, stop the infusion immediately and notify the provider. Mild flushing and pruritus are typically managed with diphenhydramine 50 mg orally or IV. Most often VFS will resolve within 20 minutes and the vancomycin infusion may be resumed at one-half the infusion rate. With ongoing infusions, VFS can be managed with preinfusion oral diphenhydramine and by slower administration, most often over 2 hours. Reactions may occur later in therapy when patients are independent with self-administration, so ensure patients are educated about the importance of infusion rate control, signs of VFS, and actions to take. Should there be changes in the infusion administration method (e.g., gravity/manual flow control device to elastomeric pump or vice versa), I strongly recommend a follow-up home visit to ensure the patient or caregiver is educated and competent in the new method of administration.

Vancomycin is nephrotoxic so both renal function and drug levels are monitored throughout the course of treatment. Older patients are at increased risk due to age-related changes in renal function. Patients who are taking other potentially nephrotoxic medications (e.g., nonsteroidal anti-inflammatory drugs) may also be at increased risk. Nephrotoxicity can occur anytime during treatment, even in patients with stable kidney function. Vancomycin trough levels should be monitored at least weekly (Norris et al., 2019) along with serum creatinine levels. Adjustments in dosage and infusion frequency are based on laboratory findings.

It is important to draw serum trough levels just prior to the vancomycin infusion. When questionable results are obtained, such as an unexpectedly high trough level, retesting via venipuncture is recommended (Gorski et al., 2021). To maintain therapeutic levels, it is essential that doses be administered on schedule, commonly every 12 or 24 hours for intermittent infusions (Krukas et al., 2020).

Although ototoxicity is relatively uncommon, it is very important to monitor for hearing loss, dizziness, tinnitus, and vertigo. Symptoms may be transient or permanent. Permanent loss of hearing or vertigo has resulted in malpractice allegations and lawsuits. Ototoxic symptoms are more often seen in patients with excessive doses, underlying hearing loss, renal impairment, or when other ototoxic medications (e.g., furosemide, gentamicin) are also administered (Patel et al., 2022). Instruct the patient to be aware of changes in hearing, to not administer the Vancomycin, and promptly report changes in hearing to the provider.

Vancomycin is both an irritant (contributing to thrombophlebitis) and a vesicant which means extravasation of the drug outside of the vein may result in tissue injury (Gorski et al., 2017; Krukas et al., 2020). For patients receiving extended courses of vancomycin (i.e., weeks), guidelines recommend administration via a central line such as a peripherally inserted central catheter.

Vancomycin should be administered with great caution through midlines which are peripheral catheters, and only very short-term, due to increased risk for endothelial damage which may result in phlebitis and extravasation. In an animal study, vancomycin infusion via midline catheters resulted in vascular injury and premature catheter failure (Ryder et al., 2020). The midline catheter tip lies deep within the tissue. Edema and changes in skin color and temperature are relatively easy to identify when superficial veins are used, but not with deep veins. The escape of any infusing fluid has the potential to cause extensive tissue exposure before signs are visible on the skin surface. Monitor carefully for absence of a blood return, fluid leakage, erythema or blanching, swelling, localized cool skin temperature, and pain, instruct patients to self-monitor and promptly report pain, tightness, burning, or discomfort. In the presence of such signs/symptoms, vancomycin should not be administered, and the provider notified.

In the United States, vancomycin is most often administered as an intermittent infusion; however, in some countries it may be administered by continuous infusion. If a patient is referred to home care with a continuous infusion, a central line should be placed. The INS Standards clearly state, "do not use midline catheters for continuous vesicant therapy" (Gorski et al., 2021, p. S76). A recent study investigating continuous vancomycin via a long peripheral catheter (midline) was halted because of evidence of thrombosis at the catheter tip of each subject as measured by daily ultrasound (Scarano et al., 2022). The findings suggest direct chemical injury of the vein wall by the vancomycin and advise central venous access for continuous infusion.

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